Gold-filled metal for jewelry manufacture

ABSTRACT

A nickel alloy base layer, consisting substantially of copper 65 percent, nickel in the range of 10 to 18 percent and the balance zinc, has a thin, substantially pure nickel backing bonded on one side. On the other side is carried a layer of gold of suitable karat, with or without the interposition of another thinner layer of substantially pure nickel bonded between the base and to the gold to form an interliner. The interliner is used when the nickel alloy consists of nickel substantially in the range of 10 to 14 percent. The interliner is omitted when the nickel alloy consists of nickel substantially in the range of 15 to 18 percent. Bonding is performed in the solid phase by rolling.

United States Patent 2 1 2 o, s r 6/1938 liaise 02703 Appl. No. 812,941 Filed Dec. 30, 1968 Patented Sept. 21, 1971 GOLD-FILLED METAL FOR JEWELRY MANUFACTURE 6 Claims, 2 Drawing Figs.

US. Cl 29/199, 29/194 Int. Cl B32b 15/00 Field of Search 29/199, 194

References Cited UNITED STATES PATENTS 3,000,085 9/1961 Green 29/199 3,221,219 11/1965 Emers 29/199 3,367,754 2/1968 Dugan 29/199 ABSTRACT: A nickel alloy base layer, consisting substantially of copper 65 percent,-nickel in the range of 10 to 18 per cent and the balance zinc, has a thin, substantially pure nickel backing bonded on one side. On the other side is carried a layer of gold of suitable karat, with or without the interposition of another thinner layer of substantially pure nickel bonded between the base and to the gold to form an interliner. The interliner is used when the nickel alloy consists of nickel substantially in the range of 10 to 14 percent. The interliner is omitted when the nickel alloy consists of nickel substantially in the range of 15 to 18 percent. Bonding is performed in the solid phase by rolling.

PATENTED SEPZI IBII FIG.1

FIG. 2

GOLD-FILLED METAL FOR JEWELRY MANUFACTURE The usual gold-filled composite for the manufacture of jewelry preferably has a substantially pure nickel base to which a gold-filling layer is bonded. However, from time to time, there have been shortages and threatened shortages of nickel which have led to attempts to make substitutions for the nickel base. Stainless steel has been tried with inadequate results because of green stain caused by the reaction between the stainless steel and body perspiration of the wearer of the jewelry.

The invention contemplates the use of a nickel-copper-zinc alloy base having a comparatively small nickel content to prevent such staining. I have found that when the nickel content is very low, diffusion may occur of copper and zinc from the base into the gold layer. Thus, for the lower nickel content in the base, I employ a substantially pure nickel interliner between it and the gold. In all cases a substantially pure nickel-backing layer is employed on the side of the nickel alloy base opposite to the side of the base which carries the gold. By substantially pure nickel is meant approximately 9.9 to 100 percent purity.

Referring to the accompanying drawings,

FIG. 1 illustrates one form of the invention; and

F 10. 2 illustrates another form.

Similar reference characters indicate corresponding parts in the two illustrations.

Referring now more particularly to FIG. 1, there is shown at numeral 1 an alloy base layer consisting, for example, substantially of 65 percent copper, nickel in the range of to 14 percent, the balance zinc. Bonded on one (the bottom) side of the base 1 is a substantially pure nickel backing 3, which preferably has a minimum thickness of about 0.001 inch. On the other (top) side of the base 1, is bonded a substantially pure nickel interliner 5 which preferably has a minimum thickness on the order of 0.0001 inch. Bonded on top of the interliner 5 is a layer of gold 7 and the thickness of which at a minimum should be on the order of 0.001 inch. The gold may be of any desired karat, such as for example but without limitation, an alloy consisting of gold 41.65 percent, copper 38.45 percent, silver 9.55 percent, nickel 1.50 percent and zinc 8.85 percent. The total thickness of the composite is variable but preferably is between 0.008 inch to 0.012 inch.

In the case of HG. 2, the base 1 consists substantially of copper 65 percent, nickel in the range of 15 to 18 percent the balance zinc. For such a composition of the base 1 the interliner is omitted. The other layers 3 and 7 and the dimensions are substantially as in the ease of FIG. 1.

In both forms of the invention the substantially pure nickel backing 3 is provided for corrosion resistance. In the case of FIG. 1 the substantially pure nickel interlinear 5 is also provided so that undesirable diffusion of copper and zinc into the gold will be prevented. There is a greater tendency for such diffusion to occurin the case of lower nickel contents of the base, such as 10 to 14 percent. But in the FIG. 2 form the interliner is not necessary because of the increased content, such as 15 to 18 percent ofthe nickel in the base 1.

in view of the above it will be seen that the invention provides a gold-filled metal for the manufacture of jewelry which conserves nickel and avoids corrosion.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above products without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. Composite gold-filled metal, comprising an alloy base which consists of nickel in the range of approximately 10 to 18 percent, copper on the order of 65 percent and the balance zinc, a substantially pure nickel backing bonded to one side of said base, and a layer of gold bonded to the other side of the base.

2. A composite according to claim I wherein the total thickness of the composite is in the range of approximately 0.008 inch to 0.012 inch, and the minimum thicknesses of the nickel backing layer and of the gold layer are approximately 0.001 inch.

3. Composite gold-filled metal, comprising an alloy base which consists of nickel in the range of approximately 10 to 14 percent, copper on the order of 65 percent and the balance zinc, a substantially pure nickel backing bonded to one side of said base, a layer of gold on the other side of the base and a substantially pure nickel interliner between the base and the gold layer are bonded to each.

4. Gold-filled metal according to claim 3 wherein the total thickness of the composite is in the range of 0.008 inch to 0.012 inch, the minimum thicknesses of the nickel backing and gold facing are approximately 0.001 inch and the minimum thickness of said nickel interliner is approximately 0.001 inch.

5. Composite gold-filled metal, comprising an alloy base which consists of nickel in the range of approximately 15 to 18 percent, copper 65 percent and the balance zinc, a substantially pure nickel backing bonded on one side of said base, and a layer of gold bonded to the other side of the base.

6. Gold-filled metal according to claim 5 wherein the total thickness of the composite is approximately in the range of 0.008 inch to 0.012 inch, and the minimum thickness of the nickel-backing layer and of the gold layer are 0.001 inch. 

2. A composite according to claim 1 wherein the total thickness of the composite is in the range of approximately 0.008 inch to 0.012 inch, and the minimum thicknesses of the nickel backing layer and of the gold layer are approximately 0.001 inch.
 3. Composite gold-filled metal, comprising an alloy base which consists of nickel in the range of approximately 10 to 14 percent, copper on the order of 65 percent and the balance zinc, a substantially pure nickel backing bonded to one side of said base, a layer of gold on the other side of the base and a substantially pure nickel interliner between the base and the gold layer are bonded to each.
 4. Gold-filled metal according to claim 3 wherein the total thickness of the composite is in the range of 0.008 inch to 0.012 inch, the minimum thicknesses of the nickel backing and gold facing are approximately 0.001 inch and the minimum thickness of said nickel interliner is approximately 0.001 inch.
 5. Composite gold-filled metal, comprising an alloy base which consists of nickel in the range of approximately 15 to 18 percent, copper 65 percent and the balance zinc, a substantially pure nickel backing bonded on one side of said base, and a layer of gold bonded to the other side of the base.
 6. Gold-filled metal according to claim 5 wherein the total thickness of the composite is approximately in the range of 0.008 inch to 0.012 inch, and the minimum thickness of the nickel-backing layer and of the gold layer are 0.001 inch. 